The Quality Assurance Review Center (QARC) was developed to perform the quality assurance (QA) of the radiotherapy (Rad) components of Cooperative Group trials in multiple groups supported by the NCI and other organizations. It is structured to support emerging diagnostic imaging (Dl) programs and to apply new technologies to a large database repository for technical appraisal and outcome analyses. The general aim of this proposal is to continue to support the RAD Programs by maintaining an effective QA Program and quality improvement opportunities using established methods, while we explore emerging technologies for newer interactive approaches. Specifically, we will continue to perform and perfect the QA Programs. We will assist in the development of new protocols to produce unambiguous guidelines. Individual patient records will be reviewed on treatment plus a final review. Information about institution compliance will be supplied to the QA Subcommittees. The Qarc repository of large amounts of information relating to Rad trials must be digitally archived, maintained, manipulated and used for calculations of statistics, and to generate reports. Taking advantage of emerging computer technologies, new relational database management system has been created. We propose to continue development and implementation of this system. We have used Benchmarks for physics review and will continue to use protocol- specific questionnaires and benchmarks to assess how selected technical and physical problems are solved and to identify actions QARC can take to further the aims of trials. We will continue to develop a portfolio of model protocols, to assist Rad coordinator. With our support, a Diagnostic Imaging Comm. (Dl) was formed in POG. QARC will coordinate the acquisition of Dl data on protocol patients, whether or not they receive Rad. By this coordination we can reduce confusion and redundancy os submitted data. The members of the Di comm. will participate more extensively in review session at QARC, and use our database for outcome analysis and other Dl studies. We have agreed to undertake the acquisition, archiving all the DI data for all protocols in POG. The development of Teleradiography and Teleconferencing for future Virtual Review Sessions will be coordinated with the Dl Comm. QARC will continue to provide and stimulate the use of our extensive data files of over 21,000 cases as a research resource for the Groups for many types of analyses and research of technical aspects of Rad. We would like to provide an educational base for Fellows and young investigators to participate in QARC's review sessions and to undertake research opportunities utilizing the material which resides in our archives.